<!DOCTYPE html>
This test verifies fixed-pos element escapes clip correctly, and then apply clip from its true clipping container even if the container is not composited.
It succeeds if a 100x100 green box is shown below.
<div style="overflow:hidden; width:100px; height:100px;">
  <div style="transform:translateX(0); width:100px; height:100px;">
    <div style="position:relative; width:10px; height:10px; overflow:hidden;">
      <div style="will-change:transform;">Promote</div>
      <div style="position:absolute; z-index:0; top:0; left:0; width:300px; height:200px;">
        <div style="position:fixed; left:0; top:0; width:200px; height:200px; background:green;">
        </div>
      </div>
    </div>
  </div>
</div>
